Wash fluid distribution system for a dishwasher

ABSTRACT

A wash fluid distribution system for dishwashers includes a spray arm mounted in one of four quadrants of a chamber floor. The spray arms can have lengths that maintain full rotation within their respective quadrant. Spray arms can also have lengths that impinge or overlap into an adjacent quadrant during full rotation of the spray arms. Each spray arm operates with a corresponding, independently controlled wash pump system. Adjacent spray arms can rotate at a same speed in opposing clockwise or counter-clockwise directions. Spray arms can also rotate in different rotation planes. A slanted surface on the chamber floor terminates at a shared particle collection area, which is centered on the chamber floor.

BACKGROUND OF THE DISCLOSURE

The present disclosure relates generally to a dishwasher fluiddistribution system and, more specifically, to a system that includes aplurality of spray arms repositioned towards opposing chamber corners toaccommodate greater appliance widths.

Modem, built-in dishwashers have been included as standard kitchenfixtures since the 1970s. While a great number of improvements have beenmade to their construction over time, their dimensions have remainedessentially unchanged; hence, features may vary from dishwasher todishwasher, but sizes are relatively standard. Conventional dishwashersare 24-inches wide by 24-inches deep; they are conveniently received inpre-fabricated cabinet spaces. Taller dishwashers generally provide forgreater loading capacities.

Single and double drawer dishwashers are the most recent designs whichaccommodate user lifestyles. Two 24-inch drawers stack to measure aheight equal to that of a conventional dishwasher; alternatively, one ortwo 24-inch drawers install in different regions of a kitchen space. Onedrawer is oftentimes too small and two drawers are oftentimes two much.Contemporary kitchens move away from traditional trends; they adoptcabinet spaces that design around fashionable, yet practicable,appliances. The present disclosure is directed towards a 30-inchdishwasher drawer which rests immediately below a counter space, and itis directed towards a fluid distribution subsystem which sprays water inthe chamber. This drawer includes at least one rack having a greaterwidth so that a user is provided with at least 144-square-inches ofadditional rack space.

A 30-inch drawer requires a custom fluid distribution system to realizeefficient chamber coverage. Existing dishwashers which have multiplespray arms assign one arm per rack: a first spray arm placed proximateto a lower rack; and, a second spray arm placed proximate to a mounted,upper rack. Conventional spray arms (hereinafter referred to as “primaryspray arms”) have diameters that travel most of the width and depth of arack, so the corresponding jet spray tower is mounted at a center of thedishwasher. The tower delivers wash fluid to the spray arms, which thendirect the fluid through the chamber in a specific spray pattern.

The primary spray arm is not efficient for wider dishwasher drawersbecause the chamber's width is unequal to its depth. The diameter of aprimary spray arm can only approximate the depth of the dishwasher. Theprimary spray arm cannot be lengthened to cover any additional spanbecause the chamber's shorter depth precludes the arm's travel. A longerprimary spray arm will essentially collide with the front and rearchamber walls if it aims to complete a full rotation. The spray patternof a shortened or standard-sized, primary spray arm will essentiallyfail to deliver water to dishes on the outermost regions of the longerrack.

A second disadvantage to the primary spray arm system occurs when a dishinadvertently blocks the sprayer. This results in the sprayer's entirerange of motion being compromised, so no dishes in the load are cleanedand the wash cycle must be repeated. This results in inefficiencies intime and energy. Accordingly, there exists a need for a fluiddistribution system that includes a plurality of shorter, regionallyspaced spray arms that each directs a wash fluid spray pattern to thedishes supported in its corresponding region.

SUMMARY OF THE DISCLOSURE

A wash fluid distribution system for dishwashers includes four sprayarms mounted proximate opposing corners of a chamber floor. A spray armmounts to a corresponding tower in each quadrant of the chamber floor.The multiple spray arm system accommodates dishwashers having unequalwidth-by-depth dimensions. A 30-inch wide by 24-inch deep dishwasherincludes shortened spray arms, each having lengths no greater than15-inches less a maximum two-inch clearance. The clearance is measuredbetween distal ends of the four spray arms and a nearest dishwashersidewall.

One aspect of the disclosure includes spray arms having approximately 8to 11-inch lengths that maintain full rotations within their respectivequadrants. A second embodiment includes spray arms having approximately11 to 13-inch lengths that impinge a neighboring quadrant during fullrotation. There are several methods to avoid collision of spray arms:(1) rotate the spray arms at a same speed in opposing clockwise andcounter-clockwise directions; or, (2) rotate the spray arms in at leasttwo different rotation planes.

Another aspect of the disclosure is at least one slanted surface on thechamber floor. The slanted surface sloped in a same direction for atleast an entire length of the spray arm supported above it. The slantedsurface orients towards and terminates at a shared particle collectionchamber, which is centered on the chamber floor where innermost cornersof the quadrants meet.

Each spray arm runs by a corresponding, independently controlled washpump system. The wash pump systems pump wash fluid though the towers tothe spray arms, which then directs the wash fluid towards the rackspaces within their respective regions. The wash fluid drops either tothe slanted surface, where it is directed to the closest wash pump forrecirculation, or to a conical section area surrounding the particlecollection chamber, where it is directed therein for draining of soilparticles.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of a dishwasher chamber floor utilizing afluid distribution system according to one aspect of the presentdisclosure;

FIG. 2 is a top plan view of a dishwasher chamber floor utilizing afluid distribution system according to a second aspect of the presentdisclosure;

FIG. 3 is a front elevational view of a chamber body shown in FIG. 1;and,

FIG. 4 is a front elevational view of a chamber body shown in FIG. 2.

DETAILED DESCRIPTION OF THE DISCLOSURE

The present disclosure is directed to a wash fluid distribution system(hereinafter synonymously referred to as the “fluid distributionsystem”, the “spray arm system”, and the “spray arm subsystem”) for adishwasher drawer. Specifically, the disclosure is directed to athirty-inch (30-inch) dishwasher drawer. The spray arm system is mainlydesigned for purposes of even, efficient, and complete wash fluidcoverage in extended dishwashers. For purposes of the presentdisclosure, an extended width dishwasher is an automatic dishwashingappliance having a conventional 24-inch depth, but one having anextended width greater than 24-inches. The spray arm system is designedfor any dishwasher having a rectangular footprint. The fluiddistribution system can be adapted for use with dual rack dishwashershaving standard 35-inch height dimensions, or they can be utilized withsingle drawers. The present disclosure is directed to a spray arm systemfor use with one rack; however, dual rack dishwashers are alsocontemplated by this disclosure.

The chamber floor of a conventional dishwasher is square-shaped with awidth equaling its depth. A primary wash arm approximates 20-inches inlength; it extends across a majority portion of the chamber's diameter.The wash arm has a tower usually positioned centrally on the floor. Thechamber floor of the present disclosure is rectangular-shaped becauseits width is greater than its depth; hence, it requires a customizedspray arm system.

Referring now to FIG. 1, the fluid distribution system 10 disclosedherein includes a chamber floor 19 and a plurality of spray arms 12 andassociated pump mechanisms to be used with a main rack, an upper rack,or a lower rack. Each of the spray arms is shorter in length than theprimary arms used in conventional dishwashers; namely, their lengthsthat are no greater than one-half the width of the dishwasher. Thelengths are shorter because each spray arm 12 is associated with aregion or quadrant of the rack as opposed to an entire rack. Each of thespray arms 12 is spaced apart towards opposing walls, opposing ends, oropposing corners of the dishwasher compartment. FIGS. 1 and 2 are topplan views of chamber floor 19, wherein various embodiments of spatialrelationships of the spray arms are shown. Both figures show adishwasher chamber floor utilizing a fluid distribution system having atleast four spray arms 12 mounted proximate opposing chamber corners.

The embodiment of FIG. 1 includes four spray arms 12 that surround acentral, shared particle collection area 14. The collection area 14 isplaced proximate to a centerpoint of the chamber floor 10. The floor 10is divided into four quadrants 11, 13, 15, 17, each of which is about 15inches by 12 inches in size. One spray arm 12 is placed in each of thequadrants 11, 13, 15, 17. In FIG. 1, the spray arms 12 are spaced apartsuch that opposite halves of the floor 10 substantially mirror eachother.

In conventional dishwashers, an approximately two-inch clearance existsbetween the distal ends of a primary spray arm and the chamber innersidewalls. A clearance dimension (shown as reference numeral “20”) forthe present disclosure is no greater than a maximum two-inch clearance.Furthermore, no spray arm 12 in this first embodiment impinges oroverlaps onto a neighboring quadrant 11, 13, 15, 17. For example, aspray arm in quadrant 11 would not overlap into quadrants 13 and 17. Itis therefore anticipated that a length of a spray arm is no greater thanabout 11-inches for a one-inch clearance 20, and the length of the sprayarm is no greater than 10-inches for a two-inch clearance 20. There alsoexists an inside clearance dimension or distance (shown as referencenumeral “24”) between the radius swept by the distal end 16 of eachspray arm 12 and an inner dimension 25 of each of the quadrants 11, 13,15, 17. The embodiment shown in FIG. 1 includes a clearance 20 of abouttwo inches, a distance 24 of about two inches from the inside edges, anda spray arm length of about ten inches.

The spray arms 12 in the first embodiment are shown installed or mountedat substantially symmetrical spacing, but other spacings arecontemplated by the disclosure. An associated tower 30 for each sprayarm 12 mounts below the spray arm in its respective quadrant 11, 13, 15,17 where the following locations intersect: one half the clearance 20plus the spray arm's radius 32 inward of the quadrant's outermost shortedge; and, one half the clearance 24 plus the spray arm's radius inwardthe quadrant's outermost long edge. The clearances 20, the distances 24,and the radii 32 may vary for each of the four spray arms 12 in thefirst embodiment, but no spray arm ever extends beyond central axes 34,36 (which are perpendicular to each other) of the chamber floor. Morespecifically, a full rotation (shown in dotted lines in FIG. 1) of eachspray arm 12 is fully maintained within its respective quadrant 11, 13,15, 17. The diameters of spray arms 12 are dependent upon the lengths ofquadrant short edges if each spray arm is to maintain complete rotationwithin its own respective quadrant.

A second embodiment is shown in FIG. 2 to include spray arms 42 having alength 39 which sweeps a circular area having a radii 49 dependent uponthe quadrant's long edge; hence, some overlap (shown as “50”) isanticipated into neighboring quadrants. Lengths 38 of spray arms 12 inthe first embodiment are no greater than the quadrant's short edgelength minus the combined clearance 20 and distance 24. These lengthsare anticipated to fall within a range of between about 8 and 11 inches.Lengths 39 of the spray arms 42 in this second embodiment are no greaterthan the quadrant's long edge length minus twice the outside clearance48. It is anticipated that a clearance 20 is between one and two inchesfrom the chamber sidewalls 18; hence, the length 39 of each spray arm 42is between about 11 and 13 inches. FIG. 2 shows spray arms 42 having a13-inch length 39. One-inch clearances 48 exist between the distal ends46 of those spray arms 42 and the chamber sidewalls 18. The rotationalsweep of distal ends 46 (shown in dotted lines) of each spray arm 42encroach upon or overlap into the quadrant (41, 43, 45, 47) adjacent toits own quadrant's inside long edge 51. The 13-inch long spray armsprovide an approximately three-inch overlap 50. A tower 52, 53 for eachspray arm 42 mounts in its respective quadrant 41, 43, 45, 47 at theintersection of the following lines: the clearance 48 plus the spray armradius inward the outside quadrant short edge 54; and, the clearanceplus the spray arm radius inward the outside quadrant short edge.

Each of spray arms 12, 42 of each embodiment can be run either by ashared pump system or by independent pump systems. An independent pumpsystem utilizes a plurality of pumps equal to the number of spray arms;a corresponding pump works in conjunction with one spray arm. Each ofthe pumps is independently controlled to provide flexible duty cycles.There are inherent advantages to flexible duty cycles: a reduction inenergy consumption; a reduction in noise pollution; a decrease in waterusage; an increase in target wash options; and, an availability ofpartial load washings.

FIG. 3 shows a front elevational view of a dishwasher chamber 100 forthe fluid distribution embodiments shown in FIG. 1. The front spray arms102, 104 and rear spray arms (not shown) are in alignment, so a view ofthe latter pair of arms is obstructed. The front spray arms 102, 104mount to towers 30 spaced a distance from sidewalls 106, 108. The towers30 support the spray arms 102, 104 at a height slightly above thechamber floor 112. At least one rack (not shown) is supported above thespray arms 102, 104 in the chamber space 100. For dishwashers utilizingat least a second, upper rack, additional spray arms are fixed to atleast one manifold proximate to the upper rack.

Each spray arm 102, 104 utilizes its own wash pump 114, 116 that forcesa jet of wash fluid (hereinafter synonymously referred to as “water”)through the tower and outwards at least one nozzle 118 at or past itsdistal end. Certain jet system embodiments utilize a conduit thatdelivers water to a plurality of nozzles 118 spaced along the length ofeach spray arm 102, 104. The spray arms 102, 104 rotate (shown asoutlined arrows) as the wash fluid is delivered through the tower 30 toforce water to travel in patterns (shown as single-lined arrows) thatcover the entire chamber 100. The spray arms 102, 104 in FIG. 3 areshown to rotate in a clockwise direction, but counter-clockwise rotationis also contemplated by the disclosure. At least one spray arm 102 or104 can travel or rotate in the clockwise direction while the otherspray arm 102 or 104 can travel or rotate in the counter-clockwisedirection. The direction of rotation of the spray arms may beestablished by the direction of the jet system in a manner well known inthe art.

The wash fluid performs certain functions dependent on the wash cycle:it rinses dishes and removes soils in a pre-wash; it also circulatesdetergent and removes stuck on food or particles in the main wash; and,it rinses all detergent and remaining soil in the rinse period. Thespray arms 102, 104 direct wash fluid at the dishes supported on theracks. Between ten to twenty percent of water drops onto a conicalsection area 120 that delivers it to a sump 122 as part of the particlecollection area 14. The remaining water drops to a slanted surface 126in the floor 112 for recirculation.

Primary wash arms in conventional dishwashers utilize pump systems thatdownwardly slope towards sump portions that exist underneath the sprayarm's travel circumference; hence, the lowest point of the collectionchamber is typically beneath the primary spray arm on the chamber floor.Essentially, the chamber floor slopes downwards from the outside chamberwalls towards the chamber center. The slope stops at the collectionchamber. The present fluid distribution system relocates the sump 122(FIGS. 3 and 4) to a central area or region removed from underneath thespray arms 12, 42 (FIGS. 1 and 2) and 102, 104 (FIGS. 3 and 4). Slantedsurface 126 terminates past the distal end 124 of the spray arms 102,104.

Each slanted surface 126 causes fallen water to travel to the closest ofthe plurality of wash pumps 114. The water becomes coarse because itcarries soil and detergent, so eighty to ninety percent of the water isfiltered through coarse filter 115 before it is returned to therespective wash pumps 114. The wash pumps 114 re-circulate the waterduring the next wash period in the sequence selected.

The sump 122 is located at a central area of the rectangular chamberfloor 112 at the innermost quadrant corners so all the spray arms 102,104 share the same sump. The bottom wall of the sump 122 rests on thelowest point of the dishwasher chamber floor 112. The top wall of thesump 122 rests at a height below the plane in which the spray arms 102,104 rest. The conical collection area 120 surrounds the sump 122. Ten totwenty percent of the water drops in the conical collection area 120 andis directed to the sump 122 and settles into the chamber. While the sump122 prevents a re-entry of the particles collected by the sump into thedishwasher chamber 100, clean water is displaced out of the sump forrecirculation. A check valve 128 in communication with the sump 122evacuates both the particle collection area 14 and the rest of thesystem. It activates a drain pump to empty the particle and soilcontents from the sump 122.

FIG. 4 is a front view of an alternate dishwasher chamber 100 for thefluid distribution embodiment shown in FIG. 2. The spray arms are offsetin different horizontal or rotational planes to avoid contacting eachother. Thus, a height of a tower 52 associated with a front spray arm102, 104 is not equal to that of a tower 53 associated with the rear arm130, 132 behind it; hence, a first pair of towers 52 is shorter ortaller than a second pair of towers 53. There is no limitation to whichpair of towers share heights: both front towers may be of equal heightand shorter than the rear tower; or both front towers may be of equalheight and taller than the rear towers; or, a first pair of towers atopposite corners (i.e., a front and an opposing rear tower) can be afirst height while the remaining pair of towers at the other oppositecorners is of a second height, where the first and second heights aredifferent from each other.

The towers are oriented to avoid collisions in both embodiments by thelateral spatial relationship in the first embodiment; and, the verticalspatial or planar relationship in the second embodiment. The towers 52,53 for the second embodiment, however, can be equal in height if thespray arms 102, 104, 130, 132 run in certain sequences which avoid theircontacting one another. Rotational direction can also lessen chances ofspray arm collision. For example, front spray arms 102, 104 can rotatein the clockwise direction while the rear spray arms rotate in thecounter clock-wise direction. A central control maintains that the speedof rotation for each spray arm is identical for all spray arm systems.The spray arms 102, 104, 130, 132 are timed to not collide.

The present spray arm 102, 104, 132, 134 is not limited to only theembodiment shown in FIGS. 1-4; rather, a routine spray pattern can beachieved with many different spray arm designs. The spray arm can haveany of a plurality of sizes, shapes, and dimensions, s.a., e.g., planar,angled, curved, straight, bent, rounded, tapered, winged, oval, andpetal-shaped, etc.

The invention has been described with reference to the preferredembodiments. Obviously, modifications and alterations will occur toothers upon reading and understanding the preceding detaileddescription. It is intended that the invention be construed as includingall such modifications and alterations.

1. A wash fluid distribution system for dishwashers having a chamberhaving a chamber floor having a width equal to or greater than a depth,said fluid distribution system comprises: a plurality of spray arms; aparticle collection area shared by said plurality of spray arms; whereinthe chamber floor comprises four quadrants, one of each of said sprayarms is mounted in an associated one of said four quadrants of saidchamber floor.
 2. The wash fluid distribution system of claim 1, whereinsaid depth is about 24-inches and said width is greater than 24-inches.3. The wash fluid distribution system of claim 2, wherein said width isabout 30-inches.
 4. The wash fluid distribution system of claim 1,wherein each of said plurality of spray arms comprises a length that isno greater than one-half of said width of the dishwasher chamber floor.5. The wash fluid distribution system of claim 1, wherein a clearancebetween a distal end of each of said spray arms and an adjacentdishwasher sidewall is a maximum of two-inches.
 6. The wash fluiddistribution system of claim 4, wherein each of said spray armscomprises a length such that a distal end of each of said spray armsremains within its associated quadrant throughout a full rotation. 7.The wash fluid distribution system of claim 4, wherein each of said fourspray arms comprises a length that causes the spray arms to protrudeinto an adjacent quadrant during a full rotation of said spray arm. 8.The wash fluid distribution system of claim 1, wherein said spray armseach run by a corresponding wash pump system independently controlled toprovide flexible duty cycles.
 9. The wash fluid distribution system ofclaim 1, wherein said spray arms are each mounted to a respective towereach of which is fixed to said chamber floor.
 10. The wash fluiddistribution system of claim 1, wherein said spray arms each rotates ina clockwise direction.
 11. The wash fluid distribution system of claim1, wherein said spray arms each rotates in a counter-clockwisedirection.
 12. The wash fluid distribution system of claim 1, wherein atleast one of said spray arms rotates in a clockwise direction and atleast one of said spray arms rotates in a counter-clockwise direction,and wherein said spray arms rotating in opposite directions are mountedon a same side of said chamber floor.
 13. The wash fluid distributionsystem of claim 1 further comprising a slanted surface in said chamberfloor, said slanted surface is oriented towards and terminates at saidparticle collection chamber.
 14. The wash fluid distribution system ofclaim 13, further comprising a conical section area that surrounds saidparticle collection chamber, said conical section area partially formedby said slanted surface, wherein wash fluid that falls into said conicalcollection area is directed into said particle collection chamber. 15.The wash fluid distribution system of claim 1, wherein said particlecollection chamber is centrally positioned on said chamber flooradjacent to where innermost corners of said quadrants abut.
 16. The washfluid distribution system of claim 7, wherein said spray arms arevertically offset in at least two rotation planes to avoid collisionwith each other.
 17. The wash fluid distribution system of claim 1,wherein said spray arms rotate at a same speed.
 18. The wash fluiddistribution system of claim 1, wherein said plurality of said sprayarms comprises four spray arms.